Short repeated DNA sequences and gene size single copy sequences are highly organized throughout most of the human genome. This organization consists of an interspersion of both sequence classes. We wish to test the proposed biological functions of the DNA sequence organization including its possible relationship to chromatin or chromosome structure. We propose to estimate the number of interspersed repeated sequences and their distribution among different chromosomes by partial base sequencing and appropriate DNA renaturation studies. The affinity of interspersed repeated sequences toward specific DNA binding proteins will be tested. Chromatin will be fractionated according to its structure by a new chemical labeling-density gradient approach to directly examine the relationship between chromatin structure and the DNA sequence organization.